1. Field of the Invention
The invention relates to a connector which uses a bar code to facilitate discrimination between types of connectors and detection of a fit failure between the male and female housing.
2. Discussion of the Related Art
Conventionally, connectors are known in which a bar code is configured by slits in order to enable both discrimination between types of connectors and detection of fit failure. FIGS. 7 to 10 show conventional connectors similar to those disclosed in Japanese Patent Publication (Koai) HEI1-294384.
Referring to FIG. 7, the connector 1 comprises a female housing 2, and a male housing 3 which is to be inserted into a fitting hole 2a of the female housing 2. When the leading end of the male housing 3 is moved closer to or butts against an end wall 2b of the fitting hole 2a, a complete fit of the male housing 3 into the fitting hole 2a is attained. A lock groove 4 is formed in an upper portion of a circumferential wall 2c of the fitting hole 2a of the female housing 2, and a lock portion 5 is correspondingly formed on an upper face of the male housing 3. These components are locked together in a complete fit condition, so as to prevent the housing 3 from slipping off the housing 2.
A plurality of slits 6A, 6B, 6C, and 6D each having a predetermined width are opened in a side portion of the circumferential wall 2c of the female housing 2. The slits elongate vertically and are arranged in parallel to each other with gaps along the connector fitting direction. These slits 6A to 6D constitute respective bars of a bar code so as to represent a code which is specific to the connector.
The side face of the male housing 3 facing the slits 6A to 6D includes an indicating portion 7. A black coating material is applied on the indicating portion 7. In the complete fit condition, the indicating portion 7 indicates black bars in accordance with the respective widths of the slits 6A to 6D, and all of the bars constitute the bar code. Although not shown in the Figure, a male terminal piece is disposed inside the female housing 2, and a female terminal piece inside the male housing 3.
A bar-code reader is used as a reading apparatus in an inspection procedure. The bar-code reader optically reads the bar code configured by the slits 6A to 6D formed in the female housing 2 and the indicating portion 7 of the male housing 3. The bar-code reader comprises a detecting scanner 8 which performs optical scanning, and a calculation unit (not shown) which judges whether or not the fit condition is achieved based on the optical information obtained by the scanner 8 and discriminates a code associated with that type of connector in accordance with the widths of the slits 6A to 6D.
Bar-codes corresponding respectively to the kinds of connectors are previously registered in the calculation unit. The calculation unit judges which of the previously registered bar codes the optical data detected by the scanner 8 corresponds to, and specifies the kind of the connector that was inspected. When a detected output is not included in the previously registered bar codes, that is, when the detected output does not correspond to any one of the registered bar codes, the fit condition is judged to be a failure, and an alarm is issued.
In the above-described configuration, if the male housing 3 is not fitted into the female housing 2 as shown in FIG. 7(a), a light passes through all the slits 6A to 6D as shown in FIG. 7(b). As a result, no waveform is output, and the calculation unit judges that there is no corresponding bar code, i.e., that the fit is a failure.
In the case of an incomplete fit as shown in FIG. 8(a), the black color of the indicating portion 7 of the male housing 3 constitutes the black bars in the portions of the slits 6A to 6C as shown in FIG. 8(b). As a result, the scanner 8 outputs a waveform. In the last slit 6D, light from the scanner 8 passes through the slit 6D so that no waveform is output for this portion. The calculation unit searches for a bar code waveform which corresponds to the output waveform of the whole bar code, and then judges that there is no corresponding bar code, i.e., that the fit is a failure.
A complete fit condition is shown in FIG. 9(a), and the portion of the last slit 6D is filled with the black indicating portion 7 so that the portion constitutes a black bar and a complete bar code is configured. Accordingly, the scanner 8 outputs a waveform corresponding to one of the bar codes which is formally registered. As a result, the calculation unit judges that the fit condition is achieved, and discriminates the kind of the connector.
FIG. 10 shows another conventional example.
In FIGS. 7-9, the portions which are observed through the slits 6A to 6D (the indicating portion 7) are colored in black. In the connector shown in FIG. 10, the portions which are observed through the slits 6A to 6D (the indicating portion 7) are colored in a white-tone color such as silver (if the foundation color is white, the coloring is not required), and the periphery of each of the slits 6A to 6D is colored in black. That is, in the connector, a black coating material 10 is applied in a rectangular shape to the side portion of the female housing 2, and each of the slits 6A to 6D is formed in an area surrounded by the black coating material 10. The side face of the male housing 3 corresponding the slits 6A to 6D is coated with a reflective coating, such as the color silver.
The connector, the arrangement of the black coated portion, and the white portions which are observed through the slits 6A to 6D (the portions coated with the reflective coating material of silver or the like) constitutes a bar code which corresponds to a type of connector. In the case of this connector, the waveform from the scanner 8 is output in a form which is inverted from that in the above-described example.
In the example shown in FIG. 10, a detection start code 20 and a detection stop code 21 which are similarly configured by black bars are respectively applied on both the front and rear portions of the rectangular black coating material 10 so that the detection start and end of the scanner 8 are represented by the bar code. Accordingly, it is possible to perform the inspection of connectors one by one.
FIGS. 11(a), 11(b), and 12 show an example of a female housing 12 in another connector having a different shape.
The female housing 12 of the connector is the same as the female housing 2 shown in FIG. 10 in arrangement and size of the slits 6A to 6D constituting a bar code, and the like, but different in shape. Specifically, a fitting hole 12a is formed in the front portion of the female housing 12, and an end wall 12b against which a leading end of the male housing butts is disposed in the innermost portion of the fitting hole 12a. Slits 6A to 6D are formed in the side portion of a circumferential wall 12c. White portions which are observed through the slits 6A to 6D (the indicating portion of the male housing), and the remaining portion of the black coating material 10 around the slits 6A to 6D (the portion which is left as a result of the formation of the slits) constitute a bar code 30(A) of pattern A. In FIG. 12, the reference numerals are attached so as to indicate bars obtained when the bar code 30(A) of pattern A is constituted.
The bar code 30(a) of pattern A consists of black bars "B" and white bars "W" arranged in the following sequence starting from the front end side (the front end side in the fitting direction). Herein, "B1" and "W1" indicate bars with a narrower width (a width of D1), and "B2" and "W2" indicate bars with a wider width (a width of D2). EQU Pattern A="B1-W2-B1-W1-B1-W1-B2-W1-B1"
FIGS. 13(a), 13(b), and 14 show a female housing 22 of another-connector having a different shape. The female housing 22 of the connector has a shape which is somewhat different from that of the female housing 12 shown in. FIG. 11, and the arrangement and size of the slits 6A to 6D of the bar code are different from those of the pattern shown in FIG. 11. Specifically, a fitting hole 22a is formed in a front portion of the female housing 22, and an end wall 22b against which a leading end of the male housing butts is disposed in the innermost recess of the fitting hole 22a. Slits 6A to 6D are formed in the side portion of a circumferential wall 22c. White portions which are observed through the slits 6A to 6D (the indicating portion of the male housing) and the remaining portion of the black coating material 10 around the slits 6A to 6D (the portion which is left as a result of the formation of the slits) constitutes a bar code 30(C) of pattern C. In FIG. 14, the reference numerals indicate bars obtained for the bar code 30(C) of pattern C.
The bar code 30(C) of pattern C consists of black bars "B" and white bars "W" arranged in the following sequence starting from the front end side. Herein, "B1" and "W1" indicate bars with a narrower width, and "B2" and "W2" indicate bars with a wider width. EQU Pattern C="B1-W1-B1-W1-B2-W1-B1-W2-B1"
Code patterns other than these can be produced by arranging the black and white bars of two kinds (two kinds of different widths) "B1", "B2", "W1", and "W2". If the width of each bar is changed with smaller differences, more kinds of bar codes can be produced. Herein, however, the case of widths of two kinds is only described by way of example.
Conventionally, as described above, a bar code pattern is set for each different shape of connector. Since a single mode can only produce one type of housing, and since a plurality of slits 6A to 6D are arranged so as to constitute a bar code, a single mold can only produce one code pattern for any given shape of a female housing. Therefore, a distinguishing bar code pattern is set for each mold. For example, in the case where the female housing 12 shown in FIGS. 11 and 12 is to be formed, the bar code of pattern A is set, and, in the case where the female housing 22 shown in FIGS. 13 and 14 is to be formed, the bar code of pattern B is set.
For the above-mentioned reason, in the case where identically shaped connectors are required to be distinguished, it is necessary to prepare another mold having a different arrangement of slits 6A to 6D. This is not economically efficient. As a result, the number of bar code patterns cannot be increased, i.e., the number of distinguishable kinds cannot be increased. If, for example, the bar code 30(C) of pattern C shown in FIG. 14 is to be attached to the female housing 12 shown in FIGS. 11 and 12, a new mold needs to be prepared.